title: Base-mediated regio- and stereoselective intermolecular addition of alkynes to N-heterocycles.
abstract: The regio- and stereoselective addition of N-heterocycles to alkynes using KOH is reported. Formation of (Z)-isomers and their conversion to (E)-products were found to be dependent upon time as well as the choice of base. Selective attack of N-heterocycles on a more electrophilic alkynyl carbon was supported by DFT calculations, and the stereochemistry of the products was established by X-ray crystallographic studies and intramolecular cyclization of ortho-haloalkynes in indolo-[2,1-a]isoquinolines.
authors.affiliation: Synthetic Organic Chemistry Research Laboratory, Department of Chemistry, University of Delhi, Delhi 110007, India.
authors.forename: Akhilesh Kumar
authors.initials: AK
authors.lastname: Verma
authors.forename: Megha
authors.initials: M
authors.lastname: Joshi
authors.forename: Ved Prakash
authors.initials: VP
authors.lastname: Singh